1,720,976 research outputs found
Subcochlear canaliculus patterns in the pediatric and adult population: radiological findings and surgical implications
The pneumatization of the different regions of the temporal bone is strictly related to the age and the degree of development of the mastoid and the middle ear. Petrous apex pneumatization is the last step of the development of the petrous bone system. The subcochlear canaliculus is an anatomical cavity, originating in the space between the fustis and the finiculus, and connecting the round window area to the petrous apex. The aim of the present article is analyzing the trend of development of the subcochlear canaliculus pneumatization, classified through CT scan examination, in different age subgroups
Combined lateral microscopic/endoscopic approaches to petrous apex lesions: pilot clinical experiences
Surgical treatment of lesions involving the temporal bone, petrous apex, or internal auditory canal is usually performed using the classical microscopic approach that necessitates wide external incisions and soft tissue dissection. At present, the main application of endoscopic surgery is in the surgical treatment of middle ear cholesteatoma, but with the natural evolution of the technique, there will be an increasing number of applications in lateral skull base surgery
Facial nerve hemangioma of the geniculate ganglion: an endoscopic surgical approach
Facial nerve hemangiomas are rare benign tumors arising from the venous plexus surrounding the facial nerve. Surgical management of these tumors is controversial. The goal of surgery is complete tumor removal with restoration of facial nerve function and preservation of hearing, wherever possible. The approaches most used are the translabyrinthine and middle cranial fossa approaches. In this report, we describe the first facial hemangioma treated with an endoscopic transcanal approach, combined with a retroauricular transmastoid minicraniotomy for closure of the dural defect. A great auricular nerve graft was used to reconnect interrupted nerve segments. Histopathological examination confirmed the diagnosis of a hemangioma of the first genu of the facial nerve. With magnification of the structures, the transcanal endoscopic approach allowed a radical excision of the neoplasm permitting hearing function preservation, with the possibility to work with a minimally invasive approach with respect to the labyrinthine block and cochlea. Compared to a middle cranial fossa approach, the transcanal endoscopic approach avoided labyrinthine block removal and brain retraction
Response to Letter to the Editor Regarding "The Role of Endoscope in Lateral Skull Base Surgery: Fact Versus Fiction"
N/
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The Impact of the Transcanal Endoscopic Approach and Mastoid Preservation on Recurrence of Primary Acquired Attic Cholesteatoma
We aim to investigate the factors associated with recurrent disease following surgery for primary acquired attic cholesteatoma. We hypothesize that minimal invasive, mucosal sparing operation techniques have beneficial effects on the outcome in terms of recurrence.Objective:We aim to investigate the factors associated with recurrent disease following surgery for primary acquired attic cholesteatoma. We hypothesize that minimal invasive, mucosal sparing operation techniques have beneficial effects on the outcome in terms of recurrence.Study Design:Retrospective study.Setting:Tertiary referral center.Participants:A total of 110 patients presenting with primary acquired attic cholesteatoma were enrolled in the study. Patients undergoing revision surgery or a canal wall down procedure, as well as patients with residual disease were excluded from the study.Main Outcome Measures:During follow-up recurrence was assessed and classified into normal, self-cleaning retraction pockets, or recurrent cholesteatoma requiring revision surgery.Results:We observed during follow-up statistically significant decrease (p = 0.036) in the occurrence of retraction pockets and recurrence in patients operated by the transcanal endoscopic approach (n = 55, 11% re-retraction, 9% recurrence) compared with those who underwent a canal wall up procedure (n = 55, 16% re-retraction, 22% recurrence). However, the multivariate model did not demonstrate statistically significant predictors regarding the outcome. Moreover, the preservation or direct reconstruction of the ossicular chain had a beneficial effect on the outcome. We observed 11% re-retraction and 9% recurrence in cases with preserved or reconstructed ossicular chain versus 18% re-retraction and 24% recurrence (p = 0.011) in cases of nonpreserved or non-reconstructed ossicular chain. A score was established according to the intraoperative mucosal damage and correlated to the occurrence of recurrence (p = 0.02). The risk of recurrence increased by 23.6% (95% confidence interval: 3.22-48.1) with each additional mucosal damage site.Conclusion:Transcanal endoscopic approaches that preserve the mastoid may play an important role in preventing recurrence and underscores the importance of the mucosa and mastoid air cells on middle ear homeostasis
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
